


Break All the Rules an AOT Omegaverse Fanfic

by YourNerdIsShowing



Category: Shingeki no Kyojin | Attack on Titan
Genre: Alpha/Beta/Omega Dynamics, Alpha/Omega, Anal Sex, Angst, BDSM, Double Oral Penetration, Double Penetration, F/M, Gay Sex, Knotting, M/M, Marking, Mating Cycles/In Heat, Multi, Omega Verse, Oral Sex, Polyamory, Rough Oral Sex, Rough Sex, Scent Marking, Sex, Sex Toys, Shower Sex, Threesome - F/M/M, Vaginal Sex
Language: English
Status: In-Progress
Published: 2021-02-04
Updated: 2021-02-04
Packaged: 2021-03-16 16:28:41
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,993
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29210385
Author URL: https://archiveofourown.org/users/YourNerdIsShowing/pseuds/YourNerdIsShowing
Summary: You’re an Omega about to be mated off on your eighteenth birthday never to be with your boyfriend Armin again because he is a Beta and he has accepted fate. You however are stuck in the middle…. You want to be with Eren but he is not of age yet and the Elders make no exceptions. So you set your sights on Levi the unmatable Alpha but Eren will stop at nothing to be with you…. What’s going to happen in this love triangle erm love square I’m not even sure myself! Guess you’ll just have to read it!
Relationships: Armin Arlert/Reader, Eren Yeager/Reader, Levi Ackerman & Reader
Kudos: 9





	Break All the Rules an AOT Omegaverse Fanfic

Omega Rule 20: On an Omega's eighteenth birthday they must be mated off to an Alpha.  
You woke up early that morning whimpering from a knot in your stomach. Today was your eighteenth birthday, come tonight you would be mated off to an Alpha but you didn’t want to be you were so happy with your boyfriend Armin.  
You laid there in silence looking at the sweet blond wrapped around you. A tear fell down your pale skin as you twirled his soft hair around your finger. “Armin…..” You sighed as more tears stained your cheeks. You held him tightly crying in silence trying not to wake up Armin.  
You felt the knot in your stomach start to pulse and between your legs became slick. “Oh just fucking wonderful.” You grumbled.  
Armin sniffed the air and instantly woke up. “You're about to go into heat (Y/N).”  
“Well thank you captain obvious.” You laughed.  
Armin pinned you to the bed. “Would you like some relief my love?” He asked slipping his hand between your legs making you whimper as he pushed a couple of fingers inside you.  
“Y-yes Armin p-please.” You wined out as he fingered you.  
“As you wish My Queen.” Armin parted your legs and went down on you instantly giving you relief as he licked your swollen clit.  
Omega Rule 34: When a female becomes fourteen she will find a boyfriend.  
In your pack females find a boyfriend of their choosing when they turn fourteen. They want you to explore yourself early so you know what you like and what you dislike. The pack you come from is well known to breed beautiful and strong Omega's who aren’t afraid to speak their minds.  
You have been with Armin since you were fourteen years old and when you turned sixteen you found out you were an Omega Armin still stayed with you. He knew you better than anyone, he knew what turned you on, how to touch you in all the right ways. It was a shame that he wasn’t an Alpha you would marry him in an instant.  
You laid there in a daze lost in your thoughts crying your eyes out as Armin pleasured you. Suddenly you were jolted out of your thoughts when you felt Armin push a toy inside you. “Ah-ahhhh Ar-Armin.” You moaned out.  
He looked at you and smiled as he thrusted the dildo in and out of you. “I wish it was me giving you this pleasure not a toy.” He chuckled trying to make you feel better.  
Omega Rule 42: Females can engage in any sexual activity EXCEPT sexual intercourse for their first time must be with their mate.  
“I wish the same thing but we know the rules you can do anything to me but have sex. I must remain a virgin.” You quoted sarcastically and laughed. “Thank goodness I have that body wash that gets rid of male pheromones or we would be screwed.” You laughed again.  
“Mhmmmm.” Armin replied before going back down on you.  
You whined out in pleasure tugging on Armin's soft hair as he licked up your juices slowly pumping the dildo in and out of you. Your body moved with every thrust as he went deeper and deeper.  
“A-Arminnnn I’m-I'm going to cummmmm!” You moaned out as you arched your back gushing into his mouth.  
Armin came up and kissed you deeply. “At least I was able to pleasure you one last time (Y/N).” He looked at you and started to cry. “I'm going to miss you so much (Y/N) why does fate have to be so cruel to us?”  
“I know my love…. I know, but I have good news for you remember that Omega's are allowed to bring a member from their pack for comfort and my sweet Armin I chose you.” You smiled and kissed him.  
“Really you did?” He got all excited.  
“Yes! I can’t imagine my life without you in it Armin.” You said happily.  
Suddenly there was a knock on the door.  
“Mikasa? Is that you?” You called out.  
“Yes it’s me (Y/N) can I come in?”  
“Uhhhh gimme a minute gotta put clothes on! Come on Armin lets get dressed.” You scrambled around and quickly got dressed.  
Armin opened the door. “Good morning Mikasa!” He said happily.  
“You're in an awfully good mood Armin, (Y/N) must have given you to good news.”  
“Indeed she did!”  
“I’m glad you’re going with her, keep her safe Armin.”  
“You know I’ll protect her with my life.”  
“I know you will, now I'm glad you’re here I want a males opinion on what (Y/N) should wear to her party and seeing that you’re her boyfriend I know you’ll pick something beautiful for her.” Mikasa turned to you. “Now time for you to get your ass in that shower so you don’t smell like Armin.”  
“Yes Ma'am!” You looked to Armin. “One last shower with me?”  
Armin picked you up. “Like you even have to ask!” He brought you to the bathroom and started to undress you. “I wish I was an Alpha this isn’t fair (Y/N) you’re my soul mate.” Armin wrapped his arms around you, as he leaned in to kiss your neck he let out a low growl.  
“Shhhhh Armin don’t say that too loud.” Your eyes started to tear up again. “It’s hard enough for the both of us right now please don’t make it harder Armin.”  
“I’m sorry I can’t help myself….” He took a deep breath in. “I need to be happy for you.” He let go of you and went to turn on the shower.  
You came up behind Armin wrapping your arms around him. “I love you so much Armin…..” You pulled him in closer to you as one of your hands traveled down towards his member making him moan softly. “Let me give you pleasure one last time as well.” You said as you pushed him into the shower. You kissed his lips tenderly.  
He kissed you back roughly as he grabbed at your butt pushing his body closer to you. He started to growl again his eyes went from blue to amber and lust-filled. He was quickly losing his senses grabbing at your body rougher by the minute as he tried to slip his member inside you.  
You growled back at Armin giving him a disgruntled look. “Armin!” You pushed him off of you. “What in the hell are you doing?”  
He looked at you narrowing his eyes as he continued to growl.  
You smacked him. “Armin! Pull yourself together! You’re better than this!”  
He shook his head and looked at you his eyes turned back to their beautiful ocean blue. “I’m-I’m sorry (Y/N)…. I lost control of myself.” He looked at you embarrassed. “You're just-just so irresistible right now because you’re in heat.” He went to grab at you again but you swatted his hands away.  
“Armin!” You wrapped your hands around his neck. “Behave!”  
“S-sorry, sorry! I’ll behave.”  
“Good boy.” You lowered yourself to Armin's length.  
Armin moaned out as you licked his pulsing member. “Oh-ohhhhhh (Y/NNNNN).” He whimpered as you took his length in its entirety down your throat.  
Mikasa knocked on the door. “Hey! I can hear you! No funny business (Y/N)!”  
You completely ignored her and continued to pleasure Armin.  
He gently gripped your hair watching on in wonder as your head bobbed up and down.  
You slowed down the pace making Armin whimper at every lick. Up and down you ran your tongue along his shaft driving him crazy.  
“Ah-ahhhhh (Y/N) I'm-I'm go-going to-to-to cummmm.” He whined as he released himself.  
You came up and kissed him. “Okay let’s shower.” You grabbed your shampoo and started to wash your hair.  
“So (Y/N) are there any Alpha's you have your eyes on?”  
“Ummmmm well actually yes there is two of them but only one is of age….” You turned red.  
“Who are they?”  
Omega Rule 25: Neither Alpha's or Omega's can mate before their eighteenth birthday.  
“Well one is Eren but like I said he isn’t of age yet….”  
“And the other one?” Armin asked.  
“L-Levi…..” You squeaked out.  
“SERIOUSLY LEVI!?” Armin yelled.  
“Y-yes…..” You hid your face in your hands.  
“You set your standards pretty high…. You know Levi has never shown any interest in an Omega ever. Not to sound mean but what makes you so special that you think he will choose you?”  
You thought back to the encounter you had with Levi when you first found out that you were an Omega.  
“If only you were of age now (Y/N) I would make you my Mate in this very moment.” He whispered into your ear sensually as he pinned you to the wall. “I want to say fuck the rules and take you right now my dear.” He leaned in and kissed you.  
You smiled a big smile and turned bright red as you remembered what he said to you two years ago. “Ohhhhh no reason.” You said as you turned redder.  
Armin raised an eyebrow. “You’re not telling me something (Y/N).” He growled as he cornered you against the wall. “Something happened between the two of you didn’t it?”  
“Y-yes….” You said shyly. “It was nothing bad he j-just kissed me.”  
Armin laughed. “So the unmatable Levi has taken an interest in my sweet (Y/N). This is going to be an interesting night indeed. The Elders will have a field day with this!” Armin boasted.  
You looked at Armin surprised. “Y-you're not mad?”  
“I can’t be mad you’re an Omega about to be the queen of a pack…. Your fate was sealed when you were sixteen. I knew from that day on Alpha's would be looking at you. I was worried at some point that I would lose you to an Alpha and I was ready to accept that. Thankfully I didn’t.” He smiled at you and kissed your forehead.  
You and Armin finished your shower. You brushed your teeth and dried your long beautiful (H/C) hair. You came out of the bathroom and Mikasa had dresses everywhere. “Holy shit Mikasa where in the world did these all come from!?”  
“I had them made for you.” She replied.  
“Wow thank you so much they’re beautiful!” You started to look through the gowns.  
“I think you should wear something that accentuates your breasts and butt…. Because both of them are very nice.” Said Armin.  
You laughed. “Of course you would say that! Okay you pick a few dresses you like.”  
Armin smiled. “Okay!” He picked three dresses, one was a deep blue very, very short skin tight and strapless. The second one was a Chinese style dress made from red silk with gold trim it was sleeveless with a slit on each side and showed a lot of side boob. The final dress was a purple tailored mermaid style dress with a plunging neckline and a slit up the side.  
“Armin none of these are even my taste…. I don’t dress like that ever….”  
“I’m sorry I was thinking what other men would like…..”  
“I understand that but that’s not the impression I'm trying to give off…. Plus I would be very uncomfortable in those.”  
“Okay then what would you pick?”  
You continue to look through the dresses your eyes fell on a (F/C) strapless low cut dress that was just short enough and hugged all your curves in the right places. You put the dress on and Armin's jaw almost fell off.  
“(Y/N) you are breathtaking!” Armin cooed.  
“Yes that dress fits you perfectly (Y/N).” Stated Mikasa. “The Alpha's won’t be able to stay away from you. Now what do you want to do for a hairstyle?”  
“Hmmmmm I think a French braid off to the side with flowers would look very nice. It’s classy and still shows off my neck.” You stated.  
“That would look beautiful.” Replied Armin.  
Suddenly an irresistibly musky smell wafted into your room. “I’ll catch up with you both later.” You slipped out of the dress and put on a tank top and shorts.  
Mikasa gave a dirty look as you left. “Don’t be stupid.”  
You gave her a look back. “Mikasa this is me we are talking about you know I'm a good girl.”  
“Yes but I also know how you get around him. So don’t be stupid.”  
“Let me guess Eren is here.” Said Armin.  
“Yes mommmmmm.” You said sarcastically as you left your room and ran down the hallway.  
You chased Eren's scent through the mansion all the way down to the private underground hot spring that was only for Alpha's and Omega's. You made your way in and slipped out of your clothes to put a towel on. Getting more excited by the minute you went into the hot spring but Eren was nowhere to be found.  
“What the hell? Eren where are you?” You called out.  
Someone came up behind you, swiped your towel and pushed you into the water. You surfaced ready to rip Eren a new asshole but he was still nowhere. “What the fuck!”  
Suddenly you heard Eren's laughter fill the cavern. Eren swam up behind you grabbing at your waist he pulled you in close to him. “Happy birthday beautiful.” He whispered into your ear as he scratched at your thighs.  
You shivered at his touch. “H-hi E-Eren.” You squeaked out. You turned around and saw a beautiful pair of lust-filled green eyes staring back at you.  
He smiled at you. “Hello beautiful.” He cooed pulling you in closer to him as he licked your neck sending you into a frenzy.  
“Ahhhhh Eren b-behave!” You whined out. “We-we shouldn’t be d-doing this.”  
He gave you a smug look. “And why not? I want to give you something special for your birthday (Y/N).”  
You grabbed onto to his neck attacking his lips moaning into his mouth as he groped at your butt.  
He broke the kiss. “I can’t help myself (Y/N) you’re sent is irresistible, you’re driving me mad.” He let out a small grunt as his member pushed up against you.  
Little whimpers escaped your lips as Eren rubbed up on you. “Eren please s-stop you’re making this so hard for me.” You looked at him with pleading eyes.  
“What’s so hard for you?” He asked staring deep into your eyes. He brought you over to a hidden cave.  
“T-to b-behave.”  
Eren pulled you out of the water. “Then don’t behave….” He said sensually slipping his hand between your legs making you moan as he pushed a couple of fingers inside you. “You know we are meant for each other (Y/N) you can’t deny that…. You’re all I ever think about, you’re all that I desire.” He kissed you deeply as he pumped his fingers in and out of you sending you into an uproar.  
You let out a loud howl making the cavern shake. “E-Eren p-p-please s-stop. D-d-don't do this to me.” You clawed at his back.  
He didn’t listen and continued to finger you.  
Your body gave in to him as he pumped his fingers even harder driving you crazy. “Ah-ahhhh d-damnit E-Eren.” You moaned out as you came all over his fingers.  
“That’s a good girl give in to your desires.” Whispered Eren before he went down on you. He ate you out like a ravenous animal licking up every last drop of your sweet juices. He growled nipping at your clit making you gush into his mouth.  
“Oh-ohhhhh Er-Erennnnnn!” You moaned out grabbing fistfuls of his long chestnut hair as your hips bucked wildly. You pulled on his hair tighter as you grinded against his face pushing him deeper in to you.  
He finally came up. “You're so wet…. Your body is just begging for me damnit (Y/N) I can’t take it anymore I need you.” He rubbed his member against you as he leaned in to kiss your neck, his kisses getting rougher and rougher as he nipped at your neck.  
“E-Eren be careful you can’t bite me….”  
“Fuck the rules.” He snarled. “I have half a mind to mark you right now! This isn’t fair why do you have to be older than me by three days! I swear if I have to break every rule I will make you mine (Y/N) I will find a way!” He pulled his fingers out of you and started to rub his member between your legs getting dangerously close to slipping inside you. Grunting and growling he was losing control of his senses as he clawed at your back. His eyes turned from green to blood red, his claws became sharper and his teeth grew pointed. He narrowed his eyes looking at you like a meal.  
“Eren….” You took his face in your hands pulling him closer to you. “Don’t look at me like that.” You licked his neck trying to calm him down.  
He stopped and came back to his senses. He tenderly kissed your lips. “I’m sorry if I took it too far.”  
“No you’re fine Eren…. I want you just as badly.” You smiled and kissed him back. “I enjoyed it immensely.”  
“Good I’m glad you did.” He kissed you again. “Now go get all sexy looking so I can ogle at you tonight.”  
You laughed. “Okay handsome I’ll look extra sexy just for you.” You kissed him one last time before parting ways.  
You got dressed and made your way back up to your room. “I have to take another shower.” You opened the bedroom door Mikasa and Armin were still in your room playing video games waiting for you.  
Mikasa sniffed the air. “You stink go shower you dirty girl.” She snickered.  
“Yes ma'am.” You laughed and made your way into the bathroom to get ready for tonight's party.


End file.
